Convertible knife sharpener



Feb. 21,1950 THQMPSQIN 2,498,018

CONVERTIBLE KNIFE SHARPENER Filed June 26, 1948 Patented Feb. 21, 1950CONVERTIBLE KNIFE SHARPENER Willis F. Thompson, Portland; Maine,assignor to The Alden Speares Massachusetts Sons (30., a corporation of-Application June 26, 1948, Serial No. 35,430

8 claims.

The invention relates to a convertible knife sharpener, and the objectof the invention is to provide a knife sharpener convertible into asmall packet within which the abrasive element of the sharpener iscontained and concealed, or the packet, by simple manipulation, be againconverted into a knife sharpener.

The invention can best be seen and understood by reference to thedrawings, in which Fig. 1 is a front elevation of a packet into whichthe knife sharpener is converted and within which its abrasive elementliesconcealed.

Fig. 2 is a front elevation of the knife sharpener.

Fig. 3 is a cross vertical section of the knife sharpener as shown inFig.2.

Fig. 4 is a side elevation of the interior of one of the rollers andassociated parts, and

Fig. 5 shows in cross section a detail of construction.

The type of knife sharpener to whichthe present invention relates islike that described in my co-pending application Serial No. 745,610.which matured as Patent No. 2,469,797, issued MaylO, 1949, in whichthere is a set of rollers and abrasive element rotated by the freerolling of the rollers back and forth over a supporting surface whenactuated by'the blade of the knife as it is reciprocated during itssharpening. One,

or preferably both, of the rollers is spaced from the abrasive elementto provide a bearing for the knife sharpener as it is reciprocatedduring its sharpening; also a hub against which the blade has bearingduring its sharpening.

As will presently be explained, in the present construction the side ofeach roller against which the blade has bearing, together with the hub,remains a normally fixed part while the remain.- ing body of the rolleris a part translatably inovable in or out with relation to thefixed'side of the roller and to the abrasive element. When moved in itwill assist in forming the packet as shown in Fig. 1, and when moved outasshown in Fig. 2 it forms one of the rollers of the knife sharpenerpresenting a side bearing and hub against which the knife blade hasbearing as it is' reciprocated during its sharpening as previouslyexplained. 7

Referring to the drawings: l represents the abrasive element which isflanked on its opposite sides by rollers 2 and 3, respectively. trepresents the interior side of each of the rollers which isinclined atan angle to the adjacent side of the abrasive element. Fixed to andpreferably formed integral with each side 4 of the roller is a hub 5generally frusta conical in shape which extends into a cavity 6 on theside of the abrasive element. The hub presents a peripheral surfacehaving a certain angularity to the side of the abrasive element. Theangularity of the side and that of the hub in relation to the side ofthe abrasive element are co-ordinated as referred to in my saidco-pending application. The inner end of each hub is closed by a web 7which bears against'the abrasive element at the bottom of the cavity 6.Passing through these webs and through that portion 8 of the abrasiveelement lying between its cavities is a rivet 9 the ends of which areupset against the respective webs. Thus the hub 5 and sides 4 of therollers are bound together and fixedly secured to sive element.

I!) represents the rim of each of the rollers. These rims bear treads llof rubber or like material around their peripheral surfaces.

The interior diameter of the rim of each of the rollers is larger thanthe diameter of itsfixed side l and that of the abrasive element, thusenabling the rim to be moved translatably over its fixed side and. .overthe abrasive element. This translatable movement of the rim isobtainedby manually turning it and is efiected as follows:

Substantially one longitudinal inner half of each rim [0 is fashioned bythickening the rim to provide interior circumferentially spaced cams l2each having an edge l3 angularly inclined with outward inclination tothe axis of the roller, or with the inner endof the inclined edgenearest said axis. Adjacent the inner end of each edge I3 is a finger l4and a socket l5.

Appliedto each of the rims is a cap or cover 16 which forms the outerside of the roller. Each of these caps is provided on its inner sidewith circumferentially spaced flanges H which fit telescopically withinthe rim for attaching the cover or cap to it. Though these flanges havea snug fit within the rim, the cover, when applied, is, also, securelyheld in place by a bead IT on the flanges which fits within a socket IDon the innerside'of the rim. The flanges 11 are formed toprovidecircumferentially spaced cams each having an edge I8 outwardly inclinedto the axis of the roller; or with the inner end of each cam edge nearerthe axis of the roller. Adjacent the outer end of each edge i8 is afinger l9 and a socket 20.

-- The cams, fingers and sockets on the-rim and cover, respectively, areso co-ordinated that when the cover ls properly applied to the rim thefinger the abra IS on the cover will fit within the socket 15 on therim, and finger H on the rim will fit within the socket 20 on the cover.This determines the proper and precise application of the cover to therim and when so applied the cams on the rim 'and cover will co-operateto form between their respective inclined edges l3 and I8 outwardlyinclined ways 2| within which lietabs 22 projecting from the edge of thefixed side 4 of the roller.

With the tabs 22 thus contained the rims are not only connected to thefixed sides of the rollers, but on turning the rims they will be movedtranslatably in one direction or the other dependent upon the directionof their turning. On turning in one direction they will be movedinwardly to where the two rims will cover the abrasive element and formthe packet as shown in Fig. 1, and when turned in a revers directionthey will be moved outwardly to form the rollers of the knife sharpeneras shown in Fig. 2.

The rims have a determinate amount of turning. When turned inwardly eachrim may be turned until the fingers l4 lying at the inner ends of theways 2| engage the respective tabs 22 forming stops, and when turnedoutwardly each rim may be turned until the fingers l9, lying at theouter ends of the ways 2|, engage the tabs forming stops.

In order that the inner and outer turned positions of the rim may bemaintained without back lash the edges l3, l8 of the respective camsapproach one another so close at points 23 adjacent the ends of therespective ways 2!, that they will hav pinching engagement with the tabswhen the rims and their associated covers move over the tabs as approachis made to the ends of their respective turning movements.

I claim:

1. A convertible knife sharpener comprising in combination a set ofrollers, an abrasive element interposed between the rollers, each of therollers including a fixed side occupying an angular position withrelation to the abrasive element, means for combining the said fixedsides and the abrasive element to rotate in unison, each of said rollersincluding a rim movable over the adjacent fixed side of the roller andover the abrasive ele ment whereby the combined rims of the respectiverollers will form a packet enclosing the abrasive element, and meanswhereby the rim of each roller may be connected to its fixed side andmoved tr'anslatably in or out, inwardly to assist in forming the packetand outwardly to assist in forming one of the rollers of the knifesharpener.

2. A convertible knife sharpener comprising in combination a set ofrollers, an abrasive element interposed between the rollers, each ofsaid rollers including a fixed side with hub, each fixed side and huboccupying separate though coordinated angular positions with relation tothe abrasive element, means for combining the fixed sides with hubs andthe abrasive element to rotate in unison, each of said rollers includinga rim movable over the adjacent fixed side of the roller and over theabrasive element whereby the combined rims of the respective rollerswill form a packet enclosing the abrasive element, and

means whereby the rim of each roller may be connected to its fixed sideand be moved translatably in or out, inwardly to assist in forming thepacket and outwardly to assist in forming one of the rollers of theknife sharpener,

3.;.A convertible knife. sharpener comprising in combination a set ofrollers, an abrasive element interposed between the rollers, each of therollers including a fixed side occupying an angular posi-- tion withrelation to the abrasive element, means for combining the said fixedsides and the abrasive element to rotate in unison, each of said rollersincluding a rim movable over the adjacent fixed side of the roller andover the abrasive element whereby the combined rims of the respectiverollers will form a packet enclosing the abrasive element, and meanswhereby the rim of each roller may be connected to its fixed side andmovable translatably in or out on turning the rim, inwardly to assist informing the packet on turning the rim in one direction, and outwardly toassist in formin one of the rollers of the knife sharpener on turningthe rim in a reverse direction.

4. A convertible knife sharpener comprising in combination a set ofrollers, an abrasive element interposed between the rollers, each of therollers including a fixed side occupying an angular position withrelation to the abrasive element, means for combining the said fixedsides and the abrasive element to rotate in unison, each of said roll,-ers including a rim movable over the ,adjacent fixed side of the rollerand over the abrasive element whereby the combined rims of therespective rollers will form a packet enclosing the abrasive element,tabs extending from the fixed side of each roller, and cams forming waysin which said tabs are contained by which the rim of each roller isconnected to its fixed side and movable translatably in or out onturning the rim, inwardly to assist in forming the packet on turning therim in one direction and outwardly to assist in forming one oftherollers of the knife sharpener on turning the rim in a re versedirection.

5. A convertible knife sharpener comprising in combination a set ofrollers, an abrasive element interposed between the rollers, each of therollers including a fixed side occupying an angular position withrelation to the abrasive element, means for combining the said fixedsides andthe abrasive element to rotate in unison, each of said rollersincluding a rim movable over the adja-. cent fixed side of the rollerand over the abrasive element whereby the combined rims of therespective rollers will form a packet enclosing the abrasive element,tabs extending from the fixed side of each roller, a cover closing theouter open side of each rim and forming the outer side of the roller,circumferentially spaced cam forming flanges on said cover by which itis secured to the rim, circumferentially spaced cams on the interior ofthe rim co-operating with said cams on the cover to form inclined waysin which said tabs are contained and by which the rim of each roller isconnected to its fixed side and movable translatably in or out onturning the rim, in-

' wardly to assist in forming the packeton turning the rim in onedirection and outwardly to assist informing one of the rollers of theknife sharpener on turning the rim in a reverse direction.

6. In a knife sharpener the combination comprising a rotatable abrasiveelement, a roller having a fixed side occupying an angular position withrelation to the abrasive element, means for combining the said fixedside and the abrasiveelement to rotate in unison, said roller includingalso a rim movable translatably over the adjacent fixed side of theroller and over the abrasive element, and means whereby the rim maybeech nected to the fixed side of the roller and moved translatably inor out on moving the rim, inwardly over the abrasive element on movingthe rim in one direction and outwardly to assist in forming the rolleron moving the rim in a reverse direction.

7. In a knife sharpener the combination comprising a rotatable abrasiveelement, a roller having a fixed side occupying an angular position withrelation to the abrasive element, means for combining the said fixedside and the abrasive element to rotate in unison, said roller includingalso a rim movable translatably over the adjacent fixed side of theroller and over the abrasive element, means whereby the rim may beconnected to the fixed side of the roller and moved translatably in orout on moving the rim, inwardly over the abrasive element on moving therim in one direction and outwardly to assist in forming the roller onmoving the rim in a reverse direction, and means for limiting andreleasably securing said rim in a determinate position when moved out toassist in forming said roller as aforesaid.

8. In a knife sharpener the combination comprising a rotatable abrasiveelement, a roller having a fixed side occupying an angular position withrelation to the abrasive element, means for combining the said fixedside and the abrasive element to rotate in unison, said roller includingalso a rim movable translatably over the adjacent fixed side of theroller and over the abrasive element, elements borne by said fixed sideof the roller, a cover closing the outer open side of the rim andforming the outer side of the roller, circumferentially spaced camforming flanges on said cover by which it is secured to the rim,circumferenti-ally spaced cams on the interior of the rim :co-operatingwith said cams on the cover to form inclined ways in which said elementsare contained and by which the rim of the roller is connected to itsfixed side and moved translatably in or out on turning the rim, inwardlyto assist in forming the packet on turning the rim in one direction andoutwardly to assist in forming one of the rollers of the knife sharpeneron turning the rim in a reverse direction.

WILLIS F. THOMPSON.

REFERENCES CITED The following references are of record in the NumberName Date Copland et al Sept. 11, 1928

